1 // SPDX-License-Identifier: GPL-2.0 2 3 #include "misc.h" 4 #include "error.h" 5 #include "sev.h" 6 7 #include <linux/kernel.h> 8 #include <linux/string.h> 9 #include <asm/insn.h> 10 #include <asm/pgtable_types.h> 11 #include <asm/ptrace.h> 12 #include <asm/sev.h> 13 #include <asm/trapnr.h> 14 #include <asm/trap_pf.h> 15 #include <asm/fpu/xcr.h> 16 17 #define __BOOT_COMPRESSED 18 #undef __init 19 #define __init 20 21 /* Basic instruction decoding support needed */ 22 #include "../../lib/inat.c" 23 #include "../../lib/insn.c" 24 25 /* 26 * Copy a version of this function here - insn-eval.c can't be used in 27 * pre-decompression code. 28 */ 29 bool insn_has_rep_prefix(struct insn *insn) 30 { 31 insn_byte_t p; 32 33 insn_get_prefixes(insn); 34 35 for_each_insn_prefix(insn, p) { 36 if (p == 0xf2 || p == 0xf3) 37 return true; 38 } 39 40 return false; 41 } 42 43 enum es_result vc_decode_insn(struct es_em_ctxt *ctxt) 44 { 45 char buffer[MAX_INSN_SIZE]; 46 int ret; 47 48 memcpy(buffer, (unsigned char *)ctxt->regs->ip, MAX_INSN_SIZE); 49 50 ret = insn_decode(&ctxt->insn, buffer, MAX_INSN_SIZE, INSN_MODE_64); 51 if (ret < 0) 52 return ES_DECODE_FAILED; 53 54 return ES_OK; 55 } 56 57 extern void sev_insn_decode_init(void) __alias(inat_init_tables); 58 59 /* 60 * Only a dummy for insn_get_seg_base() - Early boot-code is 64bit only and 61 * doesn't use segments. 62 */ 63 static unsigned long insn_get_seg_base(struct pt_regs *regs, int seg_reg_idx) 64 { 65 return 0UL; 66 } 67 68 static enum es_result vc_write_mem(struct es_em_ctxt *ctxt, 69 void *dst, char *buf, size_t size) 70 { 71 memcpy(dst, buf, size); 72 73 return ES_OK; 74 } 75 76 static enum es_result vc_read_mem(struct es_em_ctxt *ctxt, 77 void *src, char *buf, size_t size) 78 { 79 memcpy(buf, src, size); 80 81 return ES_OK; 82 } 83 84 static enum es_result vc_ioio_check(struct es_em_ctxt *ctxt, u16 port, size_t size) 85 { 86 return ES_OK; 87 } 88 89 static bool fault_in_kernel_space(unsigned long address) 90 { 91 return false; 92 } 93 94 #define sev_printk(fmt, ...) 95 96 #include "../../coco/sev/vc-shared.c" 97 98 void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code) 99 { 100 struct es_em_ctxt ctxt; 101 enum es_result result; 102 103 if (!boot_ghcb && !early_setup_ghcb()) 104 sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SEV_ES_GEN_REQ); 105 106 vc_ghcb_invalidate(boot_ghcb); 107 result = vc_init_em_ctxt(&ctxt, regs, exit_code); 108 if (result != ES_OK) 109 goto finish; 110 111 result = vc_check_opcode_bytes(&ctxt, exit_code); 112 if (result != ES_OK) 113 goto finish; 114 115 switch (exit_code) { 116 case SVM_EXIT_RDTSC: 117 case SVM_EXIT_RDTSCP: 118 result = vc_handle_rdtsc(boot_ghcb, &ctxt, exit_code); 119 break; 120 case SVM_EXIT_IOIO: 121 result = vc_handle_ioio(boot_ghcb, &ctxt); 122 break; 123 case SVM_EXIT_CPUID: 124 result = vc_handle_cpuid(boot_ghcb, &ctxt); 125 break; 126 default: 127 result = ES_UNSUPPORTED; 128 break; 129 } 130 131 finish: 132 if (result == ES_OK) 133 vc_finish_insn(&ctxt); 134 else if (result != ES_RETRY) 135 sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SEV_ES_GEN_REQ); 136 } 137